1. Field of the Invention
This invention relates to belt conveyors and more particularly to troughed belt conveyors including means for mounting and supporting the idler roll assemblies.
2. Description of the Prior Art
The "Stringerflex" cable stringer belt conveyor idlers previously manufactured by the Link Belt Company of Chicago, Ill. employed an angle iron base beam having an inverted 90.degree. angle section that provided dependent, diverting roll-mounting flanges. The beam extended transversely of the conveyor belt. The beam had a horizontal reach for mounting a bottom idler roll on our flange and bent up end portions for mounting side idler rolls on the other flange. The adjacent upper end portions of the angled side rolls and the horizontal bottom roll were laterally overlapped.
If a vertical plane were passed through the apex of the base beam angle between the bottom and the side rolls, the opposed surfaces of the bottom and side rolls facing and nearest to such plane would be spaced from the plane.
Instead of mounting the idler roll beams on cables, they have been mounted on a frame assembly constructed from structural shapes, including horizontal rails for mounting the base beams. These rails have been formed as box-section beams mounted with their upper flat faces disposed horizontally. With this construction, when the conveyor runs through a mine gallery, the upper flat faces of the rails collected ribbons of dust and debris dislodged from the roofs of the mine gallery.
Prior frame assemblies have included not only the aforesaid horizontal rails but have also included rail support legs or posts and cross braces or spacing members. If the posts and cross braces must be assembled or connected before transport into a mine gallery as sub-assemblies, such sub-assemblies do not stack compactly for transport into the gallery.
The use of wedges to connect separate units of a conveyor is known. One type of prior wedge has a small flange at its large end from which project parallel, tapered wedge flanges, cantilever fashion. These flanges are not connected along their lengths but their free ends are deformed to provide laterally projecting wedge-retaining projections. The conveyor units that are joined by these prior wedges are provided with inner and outer wedge-receiving apertures. The outer apertures are rectangular and their side edges can closely fit the side flanges of the wedges. However, in order to clear the projections on the free ends of the wedges during assembly of the units to be connected, the side walls of the inner apertures are more widely spaced than are the side walls of the outer apertures, in order to clear the retainer projections on the inner ends of the wedges. Since the inner apertures do not precisely laterally confine the inner ends of the wedges after assembly and before the wedges are hammered home, the inner ends of these wedges can become laterally cocked before and during the hammering operation.
Lateral cocking of these prior wedges precludes precise wedging engagement between the upper and lower edges of both wedge flanges and the upper and lower edges of the wedge-receiving apertures in the connector units to be joined by the wedges. One of the wedge flanges tightens before the other flange because as a result of the aforesaid cocking of the entire wedge one flange extends a greater distance through the wedge-receiving apertures than does the other flange.
Another known prior wedge is formed as a tapered solid bar, having a generally oval cross section along its length.